Engine with electronically controlled piston cooling jets and method for controlling the same

ABSTRACT

An engine oil system for an internal combustion engine comprises an electronic control module, an engine oil sump, an engine oil pump, an engine oil gallery, an engine oil pressure sensor, a solenoid control valve, and at least one oil receiving component. The engine oil pump is in fluid communication with the engine oil sump. The engine oil gallery is in fluid communication with at least one engine bearing and a turbocharger. The engine oil pressure sensor and at least one oil receiving component are in fluid communication with the oil gallery. The oil pressure sensor generates an output signal that is transmitted to the electronic control module. The solenoid control valve is in fluid communication with the engine oil gallery and electronic communication with the electronic control module. The solenoid control valve is moveable between at least an open position and a closed position.

TECHNICAL FIELD

The present disclosure relates to engine having electronicallycontrolled piston cooling jets, and more particularly to electronicallycontrolled piston cooling jets that may be selectively operated based onengine operating conditions and an electronic control module to controlthe piston cooling jets.

BACKGROUND

Many modern diesel engines contain piston cooling jets that spray engineoil on an underside of a piston to provide cooling to the piston. Engineoil, sometimes also referred to as engine lubrication oil or engine lubeoil, is continuously fed from an oil rail, or oil gallery to engineparts needing lubrication. For example, it is typically necessary tolubricate parts such as crank shaft and connecting rod bearings,turbochargers, and, in some engines, piston cooling jets. An oil systemas described above requires a large oil pump in order to provide therequired oil flow rates. Additionally, minimum engine oil pressurerecommended for turbochargers from various turbocharger manufacturersare often set at about twenty pounds per square inch (20 psi), a levelthat may not be met when engine oil is at operating temperature and theengine is operating at low engine speeds, or if the engine is operatingat lower engine speeds and the engine components are worn.

SUMMARY

According to one embodiment, an engine oil system for an internalcombustion engine comprises an electronic control module, an engine oilsump, an engine oil pump, an engine oil gallery, an engine oil pressuresensor, a solenoid control valve, and at least one oil receivingcomponent. The engine oil pump is disposed in fluid communication withthe engine oil sump. The engine oil gallery is disposed in fluidcommunication with at least one engine bearing and a turbocharger. Theengine oil pressure sensor is disposed in fluid communication with theoil gallery. The oil pressure sensor generates an output signal that istransmitted to the electronic control module. The solenoid control valveis disposed in fluid communication with the engine oil gallery andelectronic communication with the electronic control module. Thesolenoid control valve is moveable between at least an open position anda closed position in response to at least an output signal received fromthe electronic control module. The at least one oil receiving componentis disposed in fluid communication with the engine oil gallery.

According to another embodiment, an electronically controllable pistoncooling jet system for an internal combustion engine having anelectronic control module and at least one piston is provided. Thepiston cooling jet system comprises at least one piston cooling jet, apressure sensor, and a solenoid control valve. The piston cooling jetprovides oil to the at least one piston. The pressure sensor is in fluidcommunication with an oil supply to the at least one piston cooling jet.The pressure sensor generates an output signal indicative of fluidpressure within the oil supply. The solenoid control valve has an openposition and a closed position. The electronic control moduleoperatively controls the solenoid control valve to the open position andthe closed position based upon the output of the oil pressure sensor.

According to one process, a method of controlling an electronicallycontrollable oil receiving subsystem of an engine is provided. Theengine has an electronic control module, at least one piston, an oilpressure sensor, a solenoid control valve moveable between at least anopen position and a closed position, and at least one oil receivingcomponent. One aspect of the method generates an output signal of theoil pressure sensor indicative of engine oil pressure. The output of theoil pressure sensor is transmitted to the electronic control module. Theoil pressure indicated by the output signal of the oil pressure sensoris compared to at least a first predetermined value stored in a memoryof the electronic control module. An actuation signal transmits to thesolenoid control valve contains at least an instruction to position thesolenoid control valve in the open position when the output signal ofthe oil pressure sensor is indicative of an oil pressure greater thanthe at least a first predetermined value stored in the memory of theelectronic control module. Oil flow is provided to the at least one oilreceiving component when the solenoid control valve is in the openposition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing a portion of the engine oil systemfor an engine having electronically controlled oil receiving components.

DETAILED DESCRIPTION

FIG. 1 shows a portion of an engine oil system 10 for a diesel engine.The engine oil system comprises an engine oil sump 12 adapted to holdengine oil that is not presently circulating to other portions of theengine, and is also adapted to collect a majority of the engine oil whenthe engine is off. An oil pump 14 draws engine oil out of the engine oilsump 12 and provides a force on the engine oil to circulate the oilthroughout the rest of the engine oil system 10. An engine oil cooler 16may also be provided in the engine oil system. The engine oil cooler 16reduces the temperature of the circulating engine oil.

The engine oil system 10 additionally has an oil filter 18 that removescertain contaminates within the engine oil to prevent damage to theengine. Filtered engine oil is provided to an oil gallery 20. The engineoil gallery 20 has a pressure regulating valve 22 adapted to preventengine oil pressure from exceeding a predefined threshold. Excessivelyhigh engine oil pressure may cause damage to the engine, therefore, thepressure regulating valve allows some oil within the oil gallery 20 tobe returned to the engine oil sump 12, thus, reducing the oil pressurewithin the engine oil gallery 20. The engine oil gallery 20 is adaptedto deliver oil to engine bearings and other engine components 24 thatrequire engine oil. The engine bearings and other engine components 24that require engine oil are in fluid communication with the engine oilsump 12, such that engine oil drains from the engine bearings and otherengine components 24 to the engine oil sump 12.

The engine oil gallery 20 additionally provides engine oil to theturbocharger 26. The turbocharger 26 typically receives engine oil fromthe oil gallery 20 via an oil supply line (not shown) and is notdirectly connected to the engine oil gallery 20. The engine oil provideslubrication to at least one bearing within the turbocharger 26. Oil thatis provided to the turbocharger 26 also drains back to the engine oilsump 12, typically via an oil return line (not shown).

As shown in FIG. 1, the oil gallery 20 is in fluid communication with asolenoid control valve 28. The solenoid control valve 28 controls flowof engine oil to oil receiving components 30, shown in the form ofpiston cooling jets in FIG. 1 that provide engine oil to anon-combustion face side of engine pistons to reduce the temperature ofthe pistons. It is contemplated that each piston will have at least onepiston cooling jet, and each piston may have a plurality of pistoncooling jets. The solenoid control valve 28 is controlled by an engineelectronic control module 32 (ECM). The ECM 32 receives informationregarding the oil pressure from a pressure sensor 34. The pressuresensor 34 may be located in fluid communication with the oil gallery 20,or elsewhere along the engine oil system 10. The pressure sensor 34generates an output signal indicative of the oil pressure within theengine oil system 10. The output signal of the pressure sensor 34 may beused to derive the oil pressure, or may be a representation of the oilpressure. Based upon the information provided by the pressure sensor 34,the ECM 32 operates the solenoid control valve 28.

For example, when the pressure sensor 34 and the ECM 32 detect oilpressure below a first oil pressure threshold stored in a memory of theECM 32, the ECM 32 causes the solenoid control valve 28 to close,stopping the flow of oil to the oil receiving components 30, such aspiston cooling jets.

Similarly, when the pressure sensor 34 and the ECM 32 detect oilpressure above a second oil pressure threshold stored in a memory of theECM 32, the ECM 32 causes the solenoid control valve 28 to open,allowing oil to flow to the oil receiving components 30 such as pistoncooling jets. The first threshold and the second threshold may begenerally equal, or the first threshold may be a lower oil pressure thanthe second threshold oil pressure. Therefore, certain operatingconditions may exist when the engine oil pressure is above the firstthreshold oil pressure while the solenoid control valve 28 remainsclosed, and no oil flows to the oil receiving components.

Therefore, the use of a solenoid control valve 28 to control oil flow tothe oil receiving components 30, such as piston cooling jets or othernon-lubricating oil receiving components, may be used to help ensurethat minimum oil pressure required for the turbocharger 26 may bemaintained even in operating conditions historically known to producelow oil pressure, such as low engine speeds while the engine oil iswarm.

In addition to increasing the oil pressure, the use of a solenoidcontrol valve 28 to control oil flow to the oil receiving components 30,such as piston cooling jets, may also allow a lower volume oil pump 14to be used. A lower volume oil pump may be used as engine oil will notflow through the solenoid control valve 28 to the oil receivingcomponents 30 if oil pressure falls below the first oil pressurethreshold, therefore, a lower volume pump may be utilized to achieveminimum oil pressure required for normal engine operation. The use of alower volume oil pump 14 may also reduce a parasitic load on the enginefrom the oil pump 14, thus, increasing the fuel economy of the engine.

The solenoid control valve 28 to control oil flow to oil receivingcomponents 30 may additionally be utilized to enhance oil warm up fromcold starts. For instance, the ECM 32 may cause the solenoid controlvalve 28 to open when the engine is first started such that the oilflowing through the oil receiving components 30, such as piston coolingjets, is heated by the pistons, reducing the time required for theengine oil to reach normal operating temperatures.

Additionally, the engine oil system 10 may increase the oil changeinterval for the engine oil by decreasing work to the oil by using thesolenoid control valve 28 to control the flow of oil to oil receivingcomponents 30. Increased oil change intervals allow a vehicle having anengine with the engine oil system 10 to be in use for longer periods oftime between servicing, potentially increasing the productivity of thevehicle.

While specific embodiments have been illustrated and described, numerousmodifications come to mind without significantly departing from thespirit of the invention, and the scope of protection is only limited bythe scope of the accompanying Claims.

What is claimed is:
 1. An engine oil system for an internal combustionengine comprising: an electronic control module: an engine oil sump; anengine oil pump disposed in fluid communication with the engine oilsump; an engine oil gallery disposed in fluid communication with atleast one engine bearing and a turbocharger; an engine oil pressuresensor disposed in fluid communication with the engine oil gallery, theoil pressure sensor provided for generating an output signal to betransmitted to the electronic control module; a solenoid control valvedisposed in fluid communication with the engine oil gallery and inelectrical communication with the engine control module, the solenoidcontrol valve being moveable between at least an open position and aclosed position in response to at least an output signal received fromthe engine control module; and at least one oil receiving component influid communication with the solenoid control valve.
 2. The engine oilsystem of claim 1, wherein the solenoid control valve is moved to theclosed position when the output signal of the oil pressure sensorindicates engine oil pressure is below a first threshold.
 3. The engineoil system of claim 1 further comprising an oil cooler.
 4. The engineoil system of claim 1 further comprising an oil filter.
 5. The engineoil system of claim 1 further comprising an engine oil gallery pressureregulating valve disposed in fluid communication with the engine oilgallery and the engine oil sump, the oil gallery pressure regulatingvalve being moveable between at least an open position and a closedposition.
 6. The engine oil system of claim 5, wherein when oil pressurewithin the engine oil gallery is above a predetermined pressurethreshold, the engine oil gallery pressure regulating valve moves to theopen position and allows oil to flow from the engine oil gallery to theengine oil sump.
 7. The engine oil system of claim 1, wherein the atleast one oil receiving component comprises a piston cooling jet.
 8. Anelectronically controllable piston cooling jet system for an internalcombustion engine having an electronic control module and at least onepiston, the piston cooling jet system comprising: at least one pistoncooling jet providing oil to the at least one piston; a pressure sensorin fluid communication with an oil supply to the at least one pistoncooling jet, the pressure sensor provided for generating an outputsignal indicative of fluid pressure within the oil supply; and asolenoid control valve having an open position and a closed position,wherein the electronic control module operatively controls the solenoidcontrol valve to the open position and the closed position based uponthe output of the oil pressure sensor.
 9. The electronicallycontrollable piston cooling jet system of claim 8, wherein the solenoidcontrol valve is in the closed position when the output of the oilpressure sensor indicates engine oil pressure below a first threshold.10. The electronically controllable piston cooling jet system of claim9, wherein the solenoid control valve is in the closed position when theoutput of the oil pressure sensor indicates engine oil pressure above asecond threshold.
 11. The electronically controllable piston cooling jetsystem of claim 10, wherein the first threshold is lower than the secondthreshold.
 12. The electronically controllable piston cooling jet systemof claim 8, wherein the engine has a plurality of pistons and eachpiston has at least one piston cooling jet.
 13. A method of controllingan electronically controllable oil receiving subsystem for an engine,the engine having an electronic control module, at least one piston, anoil pressure sensor, a solenoid control valve movable between at leastan open position and a closed position, and at least one oil receivingcomponent, the method comprising: generating an output signal indicativeof the oil pressure sensor indicative of engine oil pressure;transmitting the output signal of the oil pressure sensor to theelectronic control module; comparing oil pressure indicated by theoutput signal of the oil pressure sensor to at least a firstpredetermined value stored in a memory of the electronic control module;transmitting an activation signal to the solenoid control valve, theactivation signal containing at least an instruction to position thesolenoid control valve in the open position when the output of the oilpressure sensor is greater than the at least a first predetermined valuestored in the memory of the electronic control module; and providing oilflow to the at least one oil receiving component when the solenoidcontrol valve is in the open position.
 14. The method of claim 13further comprising: comparing the output of the oil pressure sensor to asecond predetermined value stored in a memory of the electronic controlmodule, the second predetermined value being less than the firstpredetermined value; controlling the solenoid control valve to theclosed position when the output of the oil pressure sensor is less thanthe second predetermined value stored in the memory of the electroniccontrol module; and preventing oil flow to the at least one oilreceiving component when the solenoid control valve is in the closedposition.
 15. The method of claim 14, wherein the first predeterminedvalue and the second predetermined value are equal.
 16. The method ofclaim 14, wherein the first predetermined value is larger than thesecond predetermined value.
 17. The method of claim 13 furthercomprising: monitoring engine temperature information with theelectronic control module; controlling the solenoid control valve to theopen position when the monitoring of the engine temperature indicatesthe engine temperature is lower than a first predetermined enginetemperature stored in the memory of the electronic control module; andproviding oil flow to the at least one oil receiving component when thesolenoid control valve is in the open position.
 18. The method of claim13, wherein the oil receiving component comprises a piston cooling jet.